Rotationnal : curl

curl takes two arguments : a 3-d vector field depending on 3 variables.
curl returns the rotationnal of the vector, defined by:

curl([A,B,C],[x,y,z])= [$${\frac{{\partial C}}{{\partial y}}}$$ - $${\frac{{\partial B}}{{\partial z}}}$$, $${\frac{{\partial A}}{{\partial z}}}$$ - $${\frac{{\partial C}}{{\partial x}}}$$, $${\frac{{\partial B}}{{\partial x}}}$$ - $${\frac{{\partial A}}{{\partial y}}}$$]

Note that n must be equal to 3.
Input :

curl([x*z,-y^2,2*x^y],[x,y,z])

Output :

[2*x^y*log(x),x-2*y*x^(y-1),0]